generation. Descending numbering systems Register System The Register System uses both common numerals (1, 2, 3, 4) and Roman numerals (i, ii, iii, iv). The system is organized by generation, i.e., generations are grouped separately. The system was created in 1870 for use in the New England Historical and Genealogical Register published by the New England Historic Genealogical Society based in Boston, Massachusetts. Register Style, of which the numbering system is part, is one of two major styles used in the U.S. for compiling descending genealogies. (The other being the NGSQ System.) (–Generation One–) 1 Progenitor 2 i Child ii Child (no progeny) iii Child (no progeny) 3 iv Child (–Generation Two–) 2 Child i Grandchild (no progeny) ii Grandchild (no progeny) 3 Child 4 i Grandchild (–Generation Three–) 4 Grandchild 5 i Great-grandchild ii Great-grandchild (no progeny) 6 iii Great-grandchild 7 iv Great-grandchild NGSQ System The NGSQ System gets its name from the National Genealogical Society Quarterly published by the National Genealogical Society headquartered in Falls Church, Virginia, which uses the method in its articles. It is sometimes called the "Record System" or the "Modified Register System" because it derives from the Register System. The most significant difference between the NGSQ and the Register Systems is in the method of numbering for children who are not carried forward into future generations: The NGSQ System assigns a number to every child, whether or not that child is known to have progeny, and the Register System does not. Other differences between the two systems are mostly stylistic. (–Generation One–) 1 Progenitor + 2 i Child 3 ii Child (no progeny) 4 iii Child (no progeny) + 5 iv Child (–Generation Two–) 2 Child 6 i Grandchild (no progeny) 7 ii Grandchild (no progeny) 5 Child + 8 i Grandchild (–Generation Three–) 8 Grandchild + 9 i Great-grandchild 10 ii Great-grandchild (no progeny) + 11 iii Great-grandchild + 12 iv Great-grandchild Henry System The Henry System is a descending system created by Reginald Buchanan Henry for a genealogy of the families of the presidents of the United States that he wrote in 1935. It can be organized either by generation or not. The system begins with 1. The oldest child becomes 11, the next child is 12, and so on. The oldest child of 11 is 111, the next 112, and so on. The system allows one to derive an ancestor's relationship